HP11c - Swapping Internals Between Two

[DavidShenk]

I have a working 11c that looks horrible on the outside. If I bought a nonworking 11c that looked good, how easy would it be to switch the "insides" so that I would have a nice looking, functional calculator built from the two?

Thanks,
Dave

[Geoff Quickfall]

Swapping internals with the heat staked keyboards is do-able. It requires that the keyboard heat stakes are decapitated and then somehow refixed to the new bezel by:

remelting

gluing

small screws

Check out this posting and see the restoration of the aluminum bezel on a 15C in place and the swapping of a dented aluminum bezel with a donor on a 10C:

bezel restorations on a 15C and 10C

[DavidShenk]

Hi Geoff,

Thanks for the info. I may attempt that. My bad 11c looks like it was stored in a corrosive environment at some point and the keyboard background is full of areas of peeling and flaking paint.

I am also interested in your book when it comes out.

Dave

Edited: 24 Feb 2010, 2:11 p.m.

[John Robinson]

I've done heatstake removal and restoration on several 41c units, by using a small flat screw driver to lift the top off the heat stake, such that you remove the surround only, i.e. it's donut shaped, and not shearing off the whole top. Then to restore, I use a hot glue gun, squirt some glue, lick my finger, then press with my finger. The licking is to speed up the glue cooling, and prevent my finger getting burnt :-)

Cheers,
John

[Geoff Quickfall]

Johns suggestion is excellent.

I have removed the heads of the heat stakes as he describes and then dry assembled the board back and it held remarkably well without and glue application. As of yet I have not glued the system back together but will.

Additionally, because the back plate is screwed together at four points a thin sheet of dense foam cut to cover the circuit board and placed between the board and the calculator back might also relieve the stress on the decapitated heat stakes.

Cheers, Geoff

[Walter B]

Hi Geoff,

any news from your book? ETD?

Walter

[Frank Boehm (Germany)]

I carefully removed the molten (donut-shaped) part and after fixing the calc used a soldering iron with a very pointy tip - it looked like new :)